A linear particle accelerator (linac) can be used to accelerate charged subatomic particles or ions by subjecting them to a series of oscillating electric potentials in an acceleration chamber. In an exemplary linac application, the accelerated particles may be directed toward a target which, when struck by the particles, enables the generation of a photon beam that may be used in medical radiation therapy.
Typical linear accelerators include a particle source and an acceleration chamber that is kept under vacuum. In many linear accelerators, maintenance of the vacuum in the acceleration chamber is facilitated by a vacuum pump, for example, an ion pump. Many ion pumps include a Penning trap that confines electrons in the center of the Penning trap. The confined electrons then ionize gas particles that also enter the Penning trap. Once ionized, an electric field directs the ions to a getter that captures them, thus reducing the gas density in the linear accelerator.